Ppp4r2, a regulatory subunit of the protein phosphatase 4 (PPP4C), is involved in multiple biological processes. It plays a role in DNA damage response (DDR) [2], is associated with the circadian system [3], and may contribute to pathways like Hedgehog signaling [4]. It is also potentially involved in cell differentiation and survival, with implications in neuronal cells and hematopoiesis [1,2].

In neuronal cells, loss of Ppp4r2 function impairs the differentiation of the mouse motor-neuronal cell line NSC-34, an effect counteracted by SMN overexpression. Ppp4r2 may also protect NSC-34 cells from DNA damage-induced apoptosis [1]. In acute myeloid leukemia (AML), genetic inactivation of Ppp4r2 by RNAi in murine hematopoietic stem and progenitor cells and murine myeloid leukemia impairs de-phosphorylation of key DDR proteins, suggesting that the 3p microdeletion affecting Ppp4r2 may contribute to AML pathogenesis [2].

In conclusion, Ppp4r2 is crucial for processes such as neuronal cell differentiation and survival, as well as DNA damage repair in hematopoietic and leukemic cells. The use of gene knockout models in these studies has provided insights into its role in diseases like spinal muscular atrophy-related neuronal cell impairments and AML, highlighting its potential as a therapeutic target in these disease areas.